Variable-speed drive.



I. M. THURLOW VARIABLE SPEED DRIVE.

APPLICATION FILED mm: 14, l9l-5.

Patented Feb. 20,1917.

2 SHEETS-SHEET 1.

I. M. THURLOW.-

VARIABLE SPEED DRIVE. APPLICATION FILED may ms.

Patented Feb. 20, 1917.

2 SHEETSSHEET 2.

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N STAT S" ATENT orr o.

IRA M. THUBLQWgOF'BELOIII, WISCONSINyAfiSIGNQREO2P.fBJ YATES MACHINE COMPANY, OF-"BELOI'I, WISCONSIN, A'CORPORATION or; WISCONSIN.

. 'VARIABLE-SPEED- DRIVE.

Specification of Letters Patent; 'Pa tenttl Feb. 20, 1917.;

Application filed June 14, 1915. Serial No.

1 To all whom it may concern:

Be itknown that I, IRA M; THURLQW, a citizen of the United States, and resident of Beloit, in the county of Rockand State of Wisconsin, have invented certain new and 1 useful Improvements in Variab1e Speed Drives, 01' which the'following is a specification. r

The. inventionhas for its object the provision of power transmission mechanism whereby to convey power at different speeds from a drive to a driven shaft, and also for instantlystopping and starting ofthe driven shaft Without passing-through the various speeds, all in a most simple and efficient manner.

? In order that the invention may be readily understood, a perferred embodiment of the same is set forthlin the accompanyingdrawings and in the description based thereon.

As,1however, the inventionis susceptible of embodiment in other andvaried constructional forms, the drawings and description are'to betaken in an'illustrative and not in anunnecessary limiting sense;

'In the drawings V V 'Figure l is a plan view illustrating the relation ofthe several parts, I I

Fig! 2 is aside elevation, of'Fig. 1, 3Q ig; 3 is anenlarg'edsectional view on the line 3'3 ofEig. Land N f Fig. 4k is a detailed perspective viewfof one of the cams. I

Referring to thc-drawings more in detail,

35 theidrive shaftis illustrated at 11 the driven shaft at 12, while intermediate the 7 two shafts is located a countershaft 13. The drivev shaft is shown asequipped'with two belt pulleys 14:,and l5, and the drivenshaft 0 as'equipped with two beltpulleys 16 and 17. The countersh'aft is provided with four belt pulleys 18, 19, 20 and 21. It will be observed thatthe' belt p 'ulleys 14 and 1-6. are sm 'aller in diameter than their companion pulleys and 17; that as belt. pulley l8 of the I countershaft is ofapproximatelythe same diameter. as the drive pulley-14 with which it. is arranged line for, traverse by the belt 22. vThetwo pulleys 19. and upon 9 the countersh'aft are. arranged in ,line respectivelywith the pulleys l6 and 15,1the two pulleys 19 and 20 being ofsirnilar diameter. The pulley 19. is of-substanti'ally the same diameter as the pulley .16. and is ar- 5 ranged in line therewith ior trayerseby the pulley 23,'While the pulley 20 is arranged in line with the pulley l5'ior traverse by the belt 24. The smallest pulley 21 of the countershaft '13 is' in line with the largest pulley 17 of the driven shaftfthese two pulleys being connected by means of the belt 25. The

reference character. .26 designatesa rock sha'lti upon which are mounted two angle levers, one

of which has a longer-"arm 27 carrying a belt tightener roll 28 and a shorter arn129 car rying a cam roll 30 adapted to be engaged by the cam 31 mounted onthe cam shaft. 32. The second angle lever, mounted upon the shaft26 carriesby its longer arm"33 a belt tightener roll '34, whilefits shorter arm ,35. carries a roll 36, arranged to be acted upon by the cam 37. The beltiti'ghteners28 and 34am arranged to act respectively upon the V belts .22 and and 2. p l v .7

b At 38 isillustrated a. rockshaft upon which are f nountecl two i angle levers, the first of which has its longer arm 39 provided with a belt .tighte er 40 adapted to act upon 24: as clearly shownin thebelt' 23, while its shorter arm/ll hasifpiv: 'otally connected thereto: at 42 an actuating link rod 43."'Thelonger arm 44 of thesec- 0nd angle leyer carries a.belt tight'ener roll 45 arranged to act upon the belt/2 5. The shorter arrneG "of th e l'astnamed angle l e ver has pivotedthereto at47,an actuating link rodfl8. I 1 i I shaft jnpon which i are. mounted two arms, one of which, numbered 50, is pivoted at 51 to the end of 'the'link, 10d &3, andthe other arm 52 is pivoted at 5 3 to the endbof the link rod 48. The. two arms and 52carry respectively camrolls 54 and 55 adaptedto be actuated by the cams 56fand' 57 respectively. v i l f Uponthe end of the cam shaft 32., s fixed a handwheel 58 provided with a 59 by means of .which the' cam shaft be angularly adjusted to bring the several cams rolls. V

' ,It will be "observed thateach of the. cams 3 1, 37, 56'andt7 islformed as a secton or quadrant, four cams'imakingup a complete intoYo'perative engagementywith" the earn 7 Reference/character? tfldesignjates 'a rock to provide between adjacent cams a slight.

tioned by means of the. hand wheel 58 that all of the cam rollers except 36 rest intermediate the depressions 60, all of the belt tighteners except 3 1 are held out of engagement with their belts by means of their respective cams and the cam roller 36 will be off its cam in the space of slightly less than 270 between the two iapproaches thereto. The countershaft 13 will. now be running idly by transmission ofpower from the pulley 15 to the pulley 20. e

Aiirst speed is transmitted to the driven shaft 12 from the drive shaft 11 by turning the hand wheel through one-eighth revolution, whereby to bring the cam rollers and 54: into opposite recesses 60, whereupon the cams 37 and 57 will be caused to disengage the cam rollers 36 and 55, which will drop entirely off the cams into the positions indicated in Figs. 2 and 3, thus permitting the belt tighteners 341 and 415 to drop into engagement with the belts 2 1 and 25, whereupon the motion of the shaft 11 is trans 'mitted through the pulley 15, the belt 2ft and the pulley 20 to the countershaft 13 and thence through the pulley 21, the belt 25 and the pulley 17 to the driven shaft 12.

A second speed is transmitted to the driven shaft 12 by turning the hand wheel 58 through another quarter revolution, whereupon the cam 37 again engages the cam roll 36, lifting the belt tightener 34 out of engagement with the belt 24, and the cam 31 releases the cam roll 30, permitting the belt tightener 28 to drop into engagement with the belt 22. As the belt tightener 15 remains in engagement with the belt 25, the movement of the shaft 11 is transmitted through the pulley 14L the belt 22 and the pulley 18 to the countershaft 13 and thence through the pulley 21, the belt 25 and the pulley 17 to the driven shaft 12. r

The third speed of the driven shaft is obtained by turning the hand wheel 58 through another quarter revolution, whereby the cam roll is engaged by the cam 57 lifting the belt tightener 45 from the belt 25, and at the same time the cam roll 54 is disengaged from i the cam 56, permitting the belt tightener 1O to drop into engagement with the belt 23, and thereupon the shaft 12 is driven from the shaft 11 through the pulley 14, the belt 22, the pulley 18, the countershaft 13, the pulley 19, the belt 23 and the pulley 16 l A fourth speed is obtained by turning the hand wheel through another quarter revolution, whereby the cam. roll 30 is engaged. by the cam 31, lifting the belt tightener 28'out of engagement with the belt 22 while the belt tightener 40 remains in engagement with the belt 23, and the cam 37 disengages the cam roll 36 and permits the tightener 3st to drop into engagement with the belt 2e. Thus the movement of the shaft 11 is transmitted through the pulley 15, the belt at and the pulley 20 to the countershaft 13 and thence through the pulley 19, the belt 23 and the pulley 16 to the shaft 12.

At each intermediate position between the quarter revolutions of the hand wheel 58 the several cams, withone exception, are brought into such position that their respective cam rolls will rest intermediate the recesses 60, and'that one will drop entirely ofi its cam leaving its angle lever free to permit its belt tightener roll to drop into engagement with its belt.

If the active tightener be either 28 or 3 1, the countershaft 13 will be driven idly from the drive shaft 11', but if the active tighteners be either 40 or 45, both countershaft 13 and driven shaft 12 will obviously remain stationary for the lack of a driving connection with the drive shaft 11;

It follows that the. motion of the driven shaft 12 may be stopped instantly by turning'the hand wheel '58 to the nearest position intermediate the recesses 60 and without causing the driven shaft to pass through the various speeds. Likewise in starting it is only necessary to move the hand wheel from this neutral position intermediate the speeds in order to start the driven shaft at the same speed as before stopping.

Gbviously the pulleys upon the drive 7 be so arranged as to be lifted by their cams into engagement with the belts instead of dropping thereon bygravity.

I claim:

1. The combination with a drive shaft, a driven shaft, a countershaft, a plurality of pulleys of dissimilar size on each of the drive and driven shafts, pulleys of dissimilar size on thecountershaft and equal in number to the aggregate number carried by the drive and driven shafts, and belts connecting the pulleys of the countershaft with those of the drive and driven shafts in pairs, of a tightener for each of the belts, and unitary means to bring any two of the tighteners into operationupon belts lea ding to and from the countershaft.

2. The combination with a drive shaft, a. driven'shaft, a countershaft, a plurality of pulleys of dissimilar size on each of the drive and driven shafts, pulleys of dissimilar size on the countershaft and equal 13 leading to and from the countershaft.

3. The combination with a drive shaft, a

driven shaft, a countershaft, a plurality of' pulleys of dissimilar size on each'of the drive and driven shafts, pulleys of dissimilar size on the countershaft and equal in number to the aggregate number carried by the drive and driven shafts, and belts connecting the pulleys of the countershaft with those of the drive and driven shafts in pairs, of a tightener for each of the belts, another shaft and means carried by the latter shaft and arranged in difl-erent angular adjustments of the shaft to act on the belt tighteners to render effective any two of the belts leading to and from the countershaft.

4. The combination with a drive shaft, a driven shaft, a countershaft, a plurality of pulleys of dissimilar size on each of the drive and driven shafts, pulleys of dissimilar size on the countershaft and equal in number to the aggregate number carried by the drive and driven shafts, and beltsconnecting the pulleys of the countershaft with those of the drive and driven shafts in pairs, of a tightener for'eachof the belts, another shaft and cams carried by the latter shaft and arranged in different angular positions of the shaft to act on the belt tightenersto render effective any two ofthe belts'l'eading to and from the countershaft.

5. The combination with a drive shaft, a driven shaft, a countershaft, a plurality of pulleys of dissimilar size on each of the drive and driven shafts, pulleys of dissimilar size on the countershaft and equal in number to the aggregate number carried by the drive and driven shafts, and belts connecting the pulleys of the countershaft with those of the drive and driven shafts in pairs, ofa tightener for each of thebelts, another shaft and cams carried by the latter shaft and arranged in difierent angular adjustments of the shaft to act on the belt tighteners to render effective any two of the belts leading to and from the countershaft, said cams arranged in intermediate adjusted positions of the cam shaft to render ineffective the belt connection between the drive and driven shafts.

Signed at Chicago, Illinois, this 10th day of June, 1915. V p

, IRA M. THURLOW,

Witnesses:

Lewis T. GREIST, MILTON T. MILLER.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

' Washington, D. G. 

